We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
yo SOUND MOTION PICTURES
elevator which sinks into a trap on the stage. The latter method is preferable, since then the horns are automatically set in their proper position behind the screen. After the loud-speaking receivers are attached to the horns and connected in circuit a cursory test follows to check any possible errors. This is the first opportunity to produce sound through the complete system. Imperfections are immediately corrected. Comparative tests are then made between the sound reproducers on the projectors equipped, so that variations in tone can be compensated for. The receivers and horns are heard separately, and afterward in unison, to check poling. Receivers incorrectly poled give a most unpleasant effect of pressure in the ears of the listener if he is at the junction of their sound paths.
Before proceeding further it is desirable to have the screen used with the sound system in place — an obvious requisite of the talking picture, so that the sound shall seem to emanate directly from the scene of action on the screen. If the sound source is placed immediately behind the area of action in the picture the illusion is improved. To present the best illusion a special semi-porous screen is used. It permits sound from the horns located directly behind it to pass through readily. With the type of screen in use at present a small percentage of light is lost from the picture, but improvements are being made in screen equipment from time to time. With the screens in place and the horns set temporarily, acoustic tests are now made, and the system is finally checked.
Acoustic conditions of theatres are responsible for the obtaining of widely different results. Some houses give a mellow effect; others make reproduced sounds appear metallic. The shape of the interior has less effect in general than has the nature of the surface of the walls, the ceiling, and the floor. If these surfaces are hard and smooth like ordinary plaster, concrete, polished wood, or glass,